领扣简单版--最长公共前缀（Longest Common Prefix）

编写一个函数来查找字符串数组中的最长公共前缀。

如果不存在公共前缀，返回空字符串 ""。

示例 1:

输入: ["flower","flow","flight"]
输出: "fl"

示例 2:

输入: ["dog","racecar","car"]
输出: ""
解释: 输入不存在公共前缀。

说明:

所有输入只包含小写字母 a-z 。

Python3:

class Solution:
    def longestCommonPrefix(self, strs):
        """
        :type strs: List[str]
        :rtype: str
        """
        if not strs:
            return ''
        pre_com = ''
        for i in range(len(strs[0])):
            pre_com += strs[0][i]
            for string in strs[1:]:
                if string.startswith(pre_com):
                    continue
                else:
                    if pre_com == strs[0][0]:
                        return ''
                    else:
                        return pre_com[:-1]

        return pre_com
solution = Solution()
result = solution.longestCommonPrefix(["flower","flow","flight"])
print(result)